The profitability of feeding supplement depends on (apart from supplement and milk price) milk response per unit of energy in the supplement.
The milk response decreases significantly when the cow is well fed on pasture (i.e. residuals are greater than 1500-1600 kg DM/ha).
In spring/Rainy season, supplements will almost never be profitable when there is enough pasture, as the pasture left behind, due to substitution, is going to be wasted and the quality of the pastures in future rounds will be reduced.
In the dry season, supplements can be used to build cover and, in these cases, it can be profitable to feed supplements even when you have enough pasture.
Spring (Rainy Season)
Response g MS/MJ ME | g MS/kg DM at 11 ME | Residuals and average pasture cover (APC)¹ | Supplement | Other |
<3.0 | <30 | 9.5 clicks or 1800kg DM/ha. At or above APC target | Quality < 10.5 ME; Wastage 30% plus (fed in wet weather; poor stack mgt) | Pasture quality in subsequent rotations poor & less pasture grown |
3.5-5.5 | 40-55 | 8-9.5 clicks (1600-1800kg DM/ha); stop feeding at target APC. | Average quality 10-10.5 ME; Wastage 25%-30% | Supplement feeding stopped too late creating surplus |
5.5-7.5 | 60-80 | 6.5-7.5 clicks (1350-1550kg DM/ha if supplement not fed; residuals <8.0 clicks when supplement fed. | Good quality 10.5-11.0ME; Wastage 20% or less | Short term feed deficit (<10days). Supplement feeding stopped before APC cover target achieved |
8.0-12.0 | 90-130 | Residual < 6 clicks (1350kg DM/ha) if supplement not fed. When supplement fed residuals 6-7 clicks (1350-1500 kg DM/ha); APC well below target (> 300 kg DM/ha deficit). | Good quality > 10.5 ME Low wastage 15% or less (feeding maize or PKE in bins/on feed pad) | Cows grazing to < 6 clicks for 10 days plus; supplement feeding stopped in anticipation of target cover being met. Responses increase with the period of severe underfeeding (8.0g/ME at least 2 weeks; 10g/ME 4 weeks; 12g/ME 5 weeks) |
Note 1: One click = 0.5cm compressed height
Summer (Dry Season)
Response g MS/MJ ME | g MS/kg DM at 11 ME | Residuals and average pasture cover (APC)¹ | Supplement | Other |
<3.0 | <30 | Leaving more than 8.0 clicks | Or very poor quality <10.5 ME and high wastage 30% plus | Supplement fed to culls. Spared pasture lost when rains |
3.5-5.5 | 40-60 | 7.0-8.0 clicks (1500-1650kg DM/ha) | Good quality 10.5 + ME; Wastage 20-25%-30% | Supplement fed to culls; rotation length extended to 25 days + |
6.0-7.5 | 65-80 | Less than 7.0 clicks (1500kg DM/ha) residuals | Good quality 10.5-11.0 ME; Wastage 20% or less | Culls gone before supplement fed; rotation length slowed cow condition loss held or small loss |
7.5-11.0 | 90-120 | Residuals <6 clicks (1350kg DN/ha) if no supplement fed | Good quality 10.5+ ME; Low wastage 15% or less (feeding in bins/on feed pad) | If supplement not fed cows dried off – significant inc. DIM/ha; cow condition held |
Note 1: One click = 0.5cm compressed height
Very Dry Season/ Autumn
Response g MS/MJ ME | g MS/kg DM at 11 ME | Residuals and average pasture cover (APC)¹ | Supplement | Other |
<3.0 | <30 | Leaving 9.5 clicks plus (1800kg DM/ha); at or above APC | Quality <10.5 ME; wastage 30% plus (fed in wet weather; poor stack mgt) | Lactation not extended i.e. no increase in days in milk (DIM) per ha; loss pasture quality |
3.5-4.5 | 40-55 | 8.0-9.5 clicks (1600-1800kg DM/ha); stop feeding at target APC | Average quality 10.0-10.5 ME; wastage 25%-30% | DIM/ha unchanged; rotation length not slowed to build cover; residuals too high |
5.5-6.5 | 60-70 | 7.0-7.5 clicks (1500-1550kg DM/ha) residuals | Good quality 10.5-11.0 ME; wastage 20% or less | Rotation length slowed and increase in DIM/ha; cow condition and APC at calving targets met |
7.0-8.0 | 80-90 | Residuals <6 clicks (1350kg DM/ha) if no supplement fed; residuals 7 clicks (1500kg DM/ha); APC well below target | Good quality 10.8+ ME; low wastage 15% or less (feeding maize or PKE in bins/on feed pad) | If supplement not fed cows dried off – significant increase DIM/ha. Cow condition & cover targets achieved. |
Note 1: One click = 0.5cm compressed height